Presented by Barb Pecoraro. 26 x37 54 x 97 = 81* 62 =

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Transcript of Presented by Barb Pecoraro. 26 x37 54 x 97 = 81* 62 =

MultipleMultiplication

MethodsPresented by Barb Pecoraro

How can numbers with two digits be multiplied

together?

26

x3754 x 97 =

81* 62 =

Do you know how to multiply

two-digit numbers together?

Traditional

Partial Products

Lattice

Your Own

Method

I am confused

Partial Products Method 43 x 27 21 280 60+ 8001,161

Do you

recognize

this

method?I am confused.

Traditional Method

2

43 x 27 301 + 860 1,161

Do you

recogniz

e this

method?

Did your parents try to teach you

this method?

I am more confused.

Lattice Method4 3

2

7

60

21

08

28

16

1

1Do you

recogniz

ethis

method?

What?

Do you know anothermethod?

Steps for Partial Products Method

25 x 36 30 (6 x 5)

25 x 36 30 (6 x 5) 120 (6 x 20)

25 x 36 30 (6 x 5) 120 (6 x 20) 150 (30 x 5)

25 x 36 30 (6 x 5) 120 (6 x 20) 150 (30 x 5) 600 (30 x 20)

25 x 36 30 (6 x 5) 120 (6 x 20) 150 (30 x 5) + 600 (30 x 20)

25 x 36 30 (6 x 5) 120 (6 x 20) 150 (30 x 5) + 600 (30 x 20) 900

25 x 36 30 (6 x 5) 120 (6 x 20) 150 (30 x 5) + 600 (30 x 20) 900 Do you understand the

partial products method?

25 x 36 30 (6 x 5) 120 (6 x 20) 150 (30 x 5) + 600 (30 x 20) 900

Does the order of numbers multiplied together matter?

Steps forTraditional Method

3

25x 36 0 (6 x 5 = 30) Write the 0, regroup 3

3

25x 36 150 (6 x 5 = 30) Write the 0, regroup 3 ( (6 x 2) + 3 = 15)

3

25x 36 150 (6 x 5 = 30) Write the 0, regroup 3 0 ( (6 x 2) + 3 = 15) Write a 0; Cross out 3

1 3

25x 36 150 (6 x 5 = 30) Write the 0, regroup 3 50 ( (6 x 2) + 3 = 15) Write a 0; Cross out 3 (3 x 5 = 15) Write the 5; regroup 1

1 3

25x 36 150 (6 x 5 = 30) Write the 0, regroup 3 750 ( (6 x 2) + 3 = 15) Write a 0; Cross out 3 (3 x 5 = 15) Write the 5; regroup 1 ( (3 x 2) + 1 = 7) Write the 7

1 3

25x 36 150 (6 x 5 = 30) Write the 0, regroup 3 750 ( (6 x 2) + 3 = 15) 900 Write a 0; Cross out 3 (3 x 5 = 15) Write the 5; regroup 1 ( (3 x 2) + 1 = 7) Write the 7 Add

1 3

25x 36 150 (6 x 5 = 30) Write the 0, regroup 3 750 ( (6 x 2) + 3 = 15) 900 Write a 0; Cross out 3 (3 x 5 = 15) Write the 5; regroup 1 ( (3 x 2) + 1 = 7) Write the 7 Add

Do you understand thetraditional method?

1 3

25x 36 150 (6 x 5 = 30) Write the 0, regroup 3 750 ( (6 x 2) + 3 = 15) 900 Write a 0; Cross out 3 (3 x 5 = 15) Write the 5; regroup 1 ( (3 x 2) + 1 = 7) Write the 7 Add

Does the order of the numbers beingmultiplied matter?

Steps for Lattice Method

Draw the lattice grid.

Write the two factors.2 5

3

6

Multiply the red digits.2 5

3

6

1

5

Multiply the green digits.2 5

3

6

1

5

0

6

Multiply the blue digits.2 5

3

6

1

5

0

6

3

0

Multiply the purple digits.2 5

3

6

1

5

0

6

3

0

1

2

Add the digits in the lane with the thin arrow.2 5

3

6

1

5

0

6

3

0

1

2

0

Start here.

Add the digits in the lane with the arrow.2 5

3

6

1

5

0

6

3

0

1

2

00

1

Add the digits in the lane with arrow.2 5

3

6

1

5

0

6

3

0

1

2

00

1

Regroup one group of ten in next lane.

Add the digits in the lane with the arrow.2 5

3

6

1

5

0

6

3

0

1

2

00

1

9

Add the digits in the lane with the arrow.2 5

3

6

1

5

0

6

3

0

1

2

00

1

9The product is 900.

The product is 900.

2 5

3

6

1

5

0

6

3

0

1

2

00

1

9

Do you understand the lattice method?

The product is 900.

2 5

3

6

1

5

0

6

3

0

1

2

00

1

9

Does the order of multiplying the digits matter?

What other methods do you use to

multiply multi-digitnumbers?

RepeatedAddition

It is your turn to try.

62x 15

Did you use thepartial products method?

62 x 15 10 (5 x 2) 20 (10 x 2) 300 (5 x 60)+600 (10 x 60) 930

Did you use thetraditional method?

62 x 15 310 +620 930

Did you use thelattice method?6 2

1

5

0

2

1

0

0

6

3

09

3 0

Pal-Pair-Sharewith a partner what you

learned aboutMultiple

Multiplication Methods.

Do you have anyquestions?

Internet Resources

http://www.superteacherworksheets.com/lattice/lattice2.pdf Lattice grid